The taxonomic distribution of homology. Shown are the percentages of clusters with KEGG homologs that have the 'best hit' in each taxonomic group. Indicated are cases where the proportion of clusters best hitting to the taxonomic group differs between 1N-unique and 2N-unique (asterisks) or between 1N-unique and shared clusters (at symbol (@)), tested as above. The inset shows the proportion of all assigned clusters that are accounted for by best-hits to Chlamydomonas reinhardtii (a subset of those which are best-hits to Viridiplantae). The differences between 1N-unique and 2N-unique, and between 1N-unique and shared clusters were significant (P < 0.002).